Recent months have seen whispers of a third model joining the i ranks, in the form of an i5-badged sedan. This week, reports out of Europe suggest the so-called i5 will instead arrive in the shape of a small people-mover.

A report in Germany's Autobild magazine points to a new range-extended electric MPV slated for a 2015 launch, featuring the same carbon fibre reinforced plastic-heavy (or "light") construction featured in the upcoming i3 and i8 models.

The report adds that power for the i5 will come from a 125kW electric motor mounted at the rear axle, mated to a small 65kW three-cylinder petrol engine that would act as a range extender.

Whether the i5 is a genuine BMW project, and whether it arrives in sedan or MPV form, the new car could prove an appealing option for buyers, with fuel consumption figures likely to land in the same range as the i8 sports car - around 3.0 l/100km.

Earlier reports have also pointed to an i4 coupe, with power reportedly provided by the same 125kW electric motor powering the i3 and the reported i5.

In the case of the i3, the 0-100km/h run is listed at 7.9 seconds, meaning the potentially lighter coupe could manage the hop in somewhere around six to seven seconds.

While the i5 coupe is reportedly scheduled for a 2015 debut, the i4 coupe is not expected to land until closer to 2020.